Re: [PATCH v5] iio: chemical: scd30: Replace manual locking with RAII locking

[Maxwell Doose]

On Fri, May 29, 2026 at 5:42 AM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> On Thu, 28 May 2026 17:29:06 -0500
> Maxwell Doose <m32285159@xxxxxxxxx> wrote:
>
> > scd30_core.c currently uses manual mutex_lock() and mutex_unlock()
> > calls. Replace them with the newer guard(mutex)() for cleaner RAII
> > patterns and to improve maintainability.
> >
> > Add new helper function scd30_trigger_handler_helper() containing
> > the critical section for scd30_trigger_handler().
> >
> > In addition, small refactor to replace "?:" operator with regular
> > if/else returns.
> >
> > Signed-off-by: Maxwell Doose <m32285159@xxxxxxxxx>
>
> Looks like you sent a version that won't build.
> > +static int scd30_trigger_handler_helper(struct iio_dev *indio_dev, int *scan_data,
> > +                                     size_t scan_data_size)
> > +{
> > +     struct scd30_state *state = iio_priv(indio_dev);
> > +     int ret;
> > +
> > +     guard(mutex)(&state->lock);
> > +
> > +     if (!iio_trigger_using_own(indio_dev))
> > +             ret = scd30_read_poll(state);
> > +     else
> > +             ret = scd30_read_meas(state);
> > +     memcpy(scan_data, state->meas, scan_data_size);
> > +
> > +     return ret;
> > +}
> > +
> >  static irqreturn_t scd30_trigger_handler(int irq, void *p)
> >  {
> >       struct iio_poll_func *pf = p;
> >       struct iio_dev *indio_dev = pf->indio_dev;
> > -     struct scd30_state *state = iio_priv(indio_dev);
> >       struct {
> >               int data[SCD30_MEAS_COUNT];
> >               aligned_s64 ts;
> >       } scan = { };
> >       int ret;
> >
> > -     mutex_lock(&state->lock);
> > -     if (!iio_trigger_using_own(indio_dev))
> > -             ret = scd30_read_poll(state);
> > -     else
> > -             ret = scd30_read_meas(state);
> > -     memcpy(scan.data, state->meas, sizeof(state->meas));
> > -     mutex_unlock(&state->lock);
> > +     ret = scd30_trigger_handler_helper_locked(indio_dev, scan.data, sizeof(scan.data));
> The call needs an update t the new naming.
>

Gah, I don't know how I missed that :/ Will update for v6.

>
> >       if (ret)
> >               goto out;
> >
>